Monday, February 11, 2008

Mexicali quake shakes western Arizona

The Yuma Sun reports no damage in the Yuma area from Friday night's 5.4 magnitude earthquake that occurred 19 miles southeast of Mexicali, on a southern extension of the San Andreas fault. The Sun also noted:

Significant earthquakes, at least 7.0 in magnitude, shook Yuma in 1915, 1934 and 1940. The 1940 quake was centered near El Centro.

The Sun on May 20, 1940, reported that the quake "rocked
buildings, crumpled bridges, ripped huge crevices in pavements and on valley farms, caused large sections of land to rise and other sections to drop a foot or two below the surface of surrounding land."

[Maps are from the US Geological Survey]

1 comment:

  1. Anonymous7:02 PM

    Lightning and Thunder From Above During an Earthquake

    The missing link between sunspots, solar eruptions and other extreme solar activity and earthquakes
    is the fact that the former cause electric discharges on the Sun which also ends up affecting the Earth's
    ionosphere. To understand this missing link, the ionosphere, the earth's crust and the atmospheric air
    between them, has to be viewed as a giant planet sized capacitor. Please take note that no analogy is
    perfect and this one is no exception.

    The ionosphere forms one "plate" of a capacitor, while the surface of the Earth forms the other. Changes
    of voltage on one plate will induce movement of charge on the other plate. This movement of massive charge
    may very well be one cause of instability in the Earth's upper crust and actually end up contributing to built up
    stress in known earthquake prone areas following extreme solar activity by causing instability in the underlying
    rock. Due to stress, the subsurface rock has become semi-conducting which leads to electrical breakdown.
    There are literally millions upon millions of volts of opposite charge building up on these plates forming
    an enormous gradient. Naturally, the dielectric material which, in this case is mostly air sandwiched
    between the ionosphere plate and the stressed rock plate on the opposite side, breaks down and allows
    charge to flow between them. Nature searches for equilibrium by relasing millions of volts in the form of
    lightning discharges that travel from one plate to the other during the earthquake which, could also helps to
    release stress in the rocks. This is stress that could have been built up for hundreds or thousands of years.

    Hence the weird ground lighting artifacts and strange luminescence reported on occasions prior to an
    earthquake event as well as the lightning discharges that can happen during an actual earthquake.
    All of these predictive factors and others such as earthquke clouds can and should be scientifically measured
    and compared, even if it's not pure tectonic plate theory.

    Armchair Geophysicist